Background: Nanotechnology has potential future for enhancing therapeutic efficacy and reducing the unwanted effects of herbal drugs. The biological research on Euphorbia species has been supported by the use of some plants in traditional medicines. Many species of Euphorbia have been reported as having strong sedative and analgesic effects. In the present research work gold nanoparticles of Euphorbia milii methanolic extract (Au-EM) were synthesized, characterized and tested for antinociceptive, muscle relaxant and sedative activities.

Methods: Au-EM was prepared by stirring 1 mM warm trihydrated tetrachloroaurate solution with E. milii methanolic extract without using any external reducing agents. The gold nanoparticles were characterized by UV-Visible spectroscopy, infrared spectrophotometery, atomic force microscopy and scanning electron microscopy while their stability was evaluated against varying pH and different volumes of sodium chloride (NaCl). The metal sensing capacity of Au-EM was tested towards cobalt, copper, lead, mercury and nickel. Au-EM was evaluated in BALB/c mice at a dose of 10 and 20 mg/kg for antinociceptive, muscle relaxant and sedative activities in comparison with the crude E. milii methanolic extract.

Conclusions: These results concluded that the gold nanoparticles improved the potency of E. milii methanolic extract and exhibited significant analgesic, muscle relaxant and sedative properties. The significant metals sensing ability and enhanced stability in different NaCl and pH solutions may enable us to explore different formulations of E. milii gold nanoparticles for potentially effective and safe nano-herbal therapy.

Fig7: Effect of NaCl on the stability of Au-EM. UV–Vis spectra showing the effect of different volumes of sodium chloride (NaCl) solution on the stability of Au-EM

Mentions:
The effect of salt (NaCl) on the stability of Au-EM was determined by varying the volume of NaCl. It was observed that by increasing the volume of 0.1 M NaCl from 50 μl to 200 μl, the size and number of gold nanoparticles changed. At 200 μl 0.1 M NaCl the peak become broad and its absorbance decreases which indicate that the nanoparticles possess less stability (Fig. 7). Under visible color observation the solution faded from colored to colorless with a final addition forming precipitate.Fig. 7

Fig7: Effect of NaCl on the stability of Au-EM. UV–Vis spectra showing the effect of different volumes of sodium chloride (NaCl) solution on the stability of Au-EM

Mentions:
The effect of salt (NaCl) on the stability of Au-EM was determined by varying the volume of NaCl. It was observed that by increasing the volume of 0.1 M NaCl from 50 μl to 200 μl, the size and number of gold nanoparticles changed. At 200 μl 0.1 M NaCl the peak become broad and its absorbance decreases which indicate that the nanoparticles possess less stability (Fig. 7). Under visible color observation the solution faded from colored to colorless with a final addition forming precipitate.Fig. 7

Background: Nanotechnology has potential future for enhancing therapeutic efficacy and reducing the unwanted effects of herbal drugs. The biological research on Euphorbia species has been supported by the use of some plants in traditional medicines. Many species of Euphorbia have been reported as having strong sedative and analgesic effects. In the present research work gold nanoparticles of Euphorbia milii methanolic extract (Au-EM) were synthesized, characterized and tested for antinociceptive, muscle relaxant and sedative activities.

Methods: Au-EM was prepared by stirring 1 mM warm trihydrated tetrachloroaurate solution with E. milii methanolic extract without using any external reducing agents. The gold nanoparticles were characterized by UV-Visible spectroscopy, infrared spectrophotometery, atomic force microscopy and scanning electron microscopy while their stability was evaluated against varying pH and different volumes of sodium chloride (NaCl). The metal sensing capacity of Au-EM was tested towards cobalt, copper, lead, mercury and nickel. Au-EM was evaluated in BALB/c mice at a dose of 10 and 20 mg/kg for antinociceptive, muscle relaxant and sedative activities in comparison with the crude E. milii methanolic extract.

Conclusions: These results concluded that the gold nanoparticles improved the potency of E. milii methanolic extract and exhibited significant analgesic, muscle relaxant and sedative properties. The significant metals sensing ability and enhanced stability in different NaCl and pH solutions may enable us to explore different formulations of E. milii gold nanoparticles for potentially effective and safe nano-herbal therapy.